Numerical prediction of the dilution process and its biological impacts in CO 2 ocean sequestration

Abstract

In order to investigate the biological impacts of the ocean sequestration of CO2 (carbon dioxide), the dilution processes of CO2 were investigated near injection points in the deep ocean. From a combined fluid-dynamics, chemical, and biological approach, a two-phase computational fluid dynamics (CFD) method with mass transfer was developed to predict droplet plume flow, the dissolution of CO2 from droplets into seawater, and the advection–diffusion of dissolved CO2 (DCO2) in the deep ocean. Changes in pH due to the concentration of DCO2 were also calculated. In addition, the isomortality concept of Auerbach et al. was incorporated to predict the lethal damage to marine organisms caused by DCO2. The simulation results suggested that the biological impacts of CO2 sequestration were insignificant in terms of mortality in both small-scale field experiments and the real-life cases we propose.